Invoices and credit notes follow the same sequence in QuickBooks. We need separate numbering sequences for invoices and credit memos without any manual involvement.

Hi simangaliso-mhis, thanks for posting on the Community 

It isn't possible to alter the automated sequential numbering of sales transactions in QuickBooks Online without manual input. Please raise any product requests over on our QuickBooks Idea Exchange Board. We'll be reviewing all ideas here and if it gets to over 50 votes, we will review them with our Product team.